1. Have a wired backup
Before taking precautions below, connect to your router with a wired PC, make sure this connection works. To prevent to be cut out, either by your own clumsiness or the (very) unlikely event of a hacker tacking over.

2. Check access rights
Disable remote admin/management capabilities and log-on options on your router. Check whether all access is protected with a password (some routers only have one admin, some two and some also user log-ins) and change them with your modem powered off.

3. Limit number of available IP-addresses on the LAN
limit the range of internal IP addresses to the number of clients you normally have on your LAN (don't forget the smartphone's).

5. Change network name and key
Change the name of your network (by default the make of the router, give it another name to make it more difficult for attackers to know the weakspots of your router). Same with the encryption protection. Choose the strongest encryption type (WPA2), use a long longer than 12 characters pass phrase.

Thanks @Kees1958. I think i have a tough wireless setup. I can make pocket filter in router. The thing is i don't know if it is torrent thing or a real threat! And this thing is far beyond average user